Since I am a beginner I have been trying different yarns with my small loom. So far I have used wool and cotton yarns. I find that I really like the look of bulky yarns on the loom. The end result of the fabric is a lot lighter than if you knitted it. When selecting these yarns I find that it works better if the bulky is closer to very bulky. Here are some of my attempts
This is a cotton yarn from hobby lobby...Baby Bee Hushabye Solid. It says size 10 knitting needles... But I do not think this works well on its own for continuous loop weaving. If you double it will work ok.
This is a yarn by Brown sheep... Lambs Pride Bulky. It is a wool and mohair blend. I love working with this yarn. I also think it creates nice texture and fabric. If only my weaving skills were better.
This yarn is by Classic Elite Yarns and is cotton. The name of the yarn is Sprout and it is part of the Verde Collection. It is a very soft yarn. So far this is the best cotton yarn I have found for a single yarn method. It produces a fabric that it more dense than the Baby bee yarn, it is just a little less dense of a weave than the lambs pride.